Animal-shears.



No. 860,159. I PATENTED JULY 16, 1907.

, J. K. STEWART.

ANIMAL SHBARS.

APPLICATION FILED NOV. 30. 1906.

ating lever and pressure transmitting fingers of differ- JOHN K. STEWART, OF CHICAGO, ILLINOIS.

ANIMAL-smeris.

Speeication of Letters Patent.

Patented .ruly 16, 1907.;

Application iled November 30,1906. Serial No. 345.680.

To all whom it may concern:

Be it known that I, .ToHN K. STEWART, a citizen of the -United States, residing at Chicago, in the county of Cook and State of Illinois, have invented new and useful Improvements in Animal-Shears, `of which the following is a speciication, reference being had to the accompanying drawings, forming a part thereof.

.This invention relates to devices of the general class of animal shears which 'are hand-directed and adapted to be power-driven, and particularly to improvements in the class of shears especially adapted for sheep-shearing.- It consists of the features of construction shown and described and set out in the claims.

In the drawings: Figure 1 is a top plan view of a sheep-shearing machine embodying this invention,

with the cap-plate removed. Fig. 2 is a section at theA line 2 2 on Fig. 1 through the entire shear, with the 'cap-plate, pressure-pin and adjusting screw in place.

Fig. 3 is a detail section at the line 3 3 on Fig. 1. i Fig. 4 is a partly sectional plan View of a portion of the operent form from that shownv in the preceding figures, section being made in a horizontal plane axial in respect to the pressure fingers. Fig. 5 is a section at the line 5 5 on Fig. 4. Fig. 6 is a section at theline 6 6 on Fig. 4. Fig. 7 is a view similar -to Fig. 4 showing another modification. Fig. 8 is a section at the line 8 8 on Fig. 7. Fig. 9 is a view similar to Fig. 2 ofthe modified form shown in Fig. 4. v

The customary parts of a tool or machine of this class are shown in conventional or familiar form, comprising the housing or base, l, including the handle-piece, 1, inclosing thel driving shaft, 2, said shaft having at Y its forward end a crank-plate, whose crank Wrist or stud, 3, engages a vertical slot, 3b, in the rear end of the cutter-operating lever, 4, which is fulcrumed intermediate its ends at the ball-and-socket joint, 5, permitting it free movement to a limited extent in all dircctions. The crank-wrist, 3, has the customary antifriction roll, 3, for relieving Ithe pressure of its engagement with the operating lever, 4.' y

7 is a comb or fixed cutter blade which is'mounted rigidly upon the under side of the base or h ousing, 1, at the forward edge of the latter.

.6 is a vibrating cutter, which is` lodged upon the upper side of the comb or xed cutter and provided with apertures, 6, atwhich it is engaged by ngers of the operating arm hereinafter described. The vibrating cutter has four equally spaced shear teeth, 6b. It is necessary that all four of these teeth should be held with equal pressure upon the comb or fixed cutter, and it is not sufiicient for this purpose that the vibrating cutter is itself rigid, because the spring of the cutting teeth of this cutter yielding separately and independently, would permit them to be individually crowded off from the ixed cutter if not individually held there on by means operative to so hold them to an extent independ ently of the other teeth. For this purpose the operating lever, 4, carries four pressure fingers bearing upon the four teeth, 6b, respectively. The necessary pressure is transmitted to the fingers through the operatinglever by means of the pressure pin or dolly, 8, having its splierical terminal, 8', at the lower end stepped in the socket,

", oi' the operating lever forward of the universal joint ful'crum of the latter. The operation of this pressure pin for transmitting pressure and permitting the oscillation of the cutter is familiar and need not be further described beyond indicating that its head or upper end 'is slightly curved and bears against the top of thesocket, 9a, in the tension screw, 9, which is screwed down through the cap for applying and varying the pressure for holding the two cutters in Contact. ,In order that ,the pressure transmitted thus from the foot of the dolly stepped in the operating lever may be distributed equally to the four fingers, the operating lever'is fulcrumed, as described,so that it is free to rock slightly about a fore-and-aft axis through-itssaid universally pivotal bearing and the pivotal step of the dolly pin upon it. `If there were but two pressure ngers this rocking movement ofthe operating lever would suice to transmit the pressure equally to such two fingers providing they were equally spaced at opposite sides of the axial line. When. a third finger only is employed in the axial line this rocking movement `is still sufficient to transmit the pressure operating lever for vertical movement, as in many familiar forms of tools of this class; but when there are four pressure fingers it will be evident that if two of them, being either the extreme or the intermediate pair, are vcarried rigidly with the operating lever, the

other two being upon a lever pivoted only for swinging vertically, the lateraloscillation orrocking of the operating lever will be defeated by the fact that such pivotal member carrying the two fingers has, by means of its two fingers, two points of bearing, and' therefore cannot serve as a pivot for the oscillating or locking movement by which-the pressure would be equalized. In order, therefore, that t'he pressure of four ngers may be equalized, I form and arrange them iin pairs, the two of-each pair being rigid-and integral with each other, the parthaving each pairy thus formed being mounted pivotally on the operating lever with capacity i for rocking about a fore-and-aft axis intermediate the two fingers which it carries.

In the form shown in Figs. 1, 2, 3 and 4, the lingers are made two pairs, one comprising the two righthand fingers, 10210, andthe other the two left-hand fingers, 10b, 10b, each pairbeing rigid and projecting from a cross-head ona spindle or stem, 10, the two spindles, 10, being mounted for rocking in sleeves or bearings, 4"; 4, situated at the end of the operating v when that finger itself is pivotally connected to the application of pressure.

lever, `4, symmetrically with respect to the fore-andaft vertical plane through the iulcrum and point of be seen that the operating lever is adapted to transmit equal pressure to the two spindles or stems, '10, l'10, and i spindle a sufficient distance to allow it the necessary` rocking movement.` (Obviously, the groove may complete` the circle of the spindle, if desired.)

In the form shown in Fig. 7, the construction is substantially similar to that already described, except that each pair of fingers consists ofthe extreme and one in- 'termediate finger; and the cross-heads from which the 'two fingers of the two pairs respectively project are formed so that one may reach over the other as is necessary in view of the distribution-'of the fingers to the two` cross-heads. In this construction it will be noticed -that the bearings for the spindles, l0, are in line with the intermediate fingers respectively in order to be respectively intermediate between the two fingers of the respective pairs. y i

In the form shown in Figs. 4, 5 and 6, the fingers are distributed into two pairs, one of which comprises the extreme fingers and the other the intermediate fingers.

The extreme fingers project from a longer cross-head, l0x having at its middle point a spindle or stem, 10y and the intermediate fingers project from a shorter crosshead, 102, having at its middle point a spindle, 10W. The spindle, 10Y, is hollow,` and the spindle, 10,seats and is journaled in it, the larger spindle being in turn -journaled in the forward end oi the operating lever, 4, so that both spindles rock about a common pivotal axis. In this construction it is not necessary that the operating lever have any rocking movement of its own, since both pairs of fingers are adapted to rock about a fore-and-ait line through the pivot of, and the point of application of pressureto, the operating lever. This lever is, however, shown withthe same form of ulcrum in these figures as in the others. In this form it is necessary to provide against either lpair of fingers taking all the pressure to the exclusion ofthe other pair, and for this purpose the pressure is applied not directly to the operating lever, 4, but to the stem of one pair of fingers, being transmitted through that stem to the other pair,-an expedient which is analogous to a familiar construction employed when there are only three fingers. A convenient method of accomplishingl this is that shown in the drawings, in which the spindle,y lOY, of-the longer cross-head .is bored out .from both ends with a taper-pointed drill, the two bores meeting so as to leave an annular D-shaped interiorly protruding bead or seat, Il, the aperture through which corresponds to the diameter of the spindle, 10W, of the" shorter cross-head, so that the latter spindle is free to oscillate in all-directions tothe limit of the full diame ter ot the bore in the spindle, 105'. To limit this oscil- By this construction, it will lation to a vertical plane but at the same time to retain the spindle, 10W, in the spindle, lOY, the spindle, 10W, has an annular groove, 12, and two pins, 13, 13, are set parallel to each other vertically through the spindle,

10V, taking into the annular groove, 13, at opposite sides of the spindle, 10W, and serving both as keys to prevent lthe withdrawal of the spindle and also as guides between Which the spindle may oscillate vertically while it is prevented from oscillating laterally. The spindle, IOY, is retained in its bearing in the operating lever'by a similar expedient, an exterior annular groove, 14, being made in the spindle and key pins, 15, l5, being set through the bearing, taking into said groove leaving the spindle free to turn for preventing it from withdrawing. .'lhe dolly pin, 8, in this construction is stepped at 16, on-the stemof the shorter cross-head at substantially one-fourth oi the distance from the pivotal bearing of thestem, 10W, on the annular bead, Il.

to the points ofthe pressure fingers which,-in view of the position of the fulcrum', 5, one-half of the same distance rearward from the step bearing, 16,-causes the pressure to be transmitted equally to all four-fingers.

In all the forms, any two,-preierably the outer.

two,-iingers have each a stud, 18, engaging the holes in the vibrating cutter for actuating it.

I claim:-

l. A shear comprising a comb or fixed cutter' and o. vlbrating cutter; adoperat'ing lever forA vibrating the vibrating cutter 'vmeans for oscillating the lever and means for applying pressure to it to press the vibrating cutter upon the fixed cutter, two pairs of pressure fingers for transmitting said pressure, each pair being pivotully mounted on the oper-ating lever for oscillation about a fol'eandaft axis midway between the two fingers of the pair. the pivotal bearings of said pairs in the operating lever being symmetrically disposed with respect to a fore and-aft' line through the pivot of the vibrating lever and the point of. application of pressure thereto.

2. A shear comprisinga comb or fixed cutter and a vibrafing cutter; an`operating rever for vibrating the vibrating cutter; means for oscillating the lever and means for applying pressure to it to pressthe vibrating cutter upon the fixed cutter; two pairs of pressure lingers for transmitting said pressure, each pair being pivotally mounted on f he operating lever for oscillation about a foreand-aft axis midway between the two fingers of the pair,

the pivotal bearings of said pairs in the operating lever being symmetrically disposed at opposite sides of a foreand-aft line through the pivot of the vibrating lever and thepoint of application of pressure thereto.

-A shear comprising a comb or fixed cutter and a vibrating cutter; an operating lever for engaging and vibrating the vibrating cutter; means for`oscil1atng the lever for.applying.pressure-:thereto to press the vibrating iisy cutter upon the fixed cutter; twopairs of fingers by means of which such pressure istransmitted, the two right-hand fingers being in one pair and the two lefthand fingers in the other pair, each-pair having a spindle or stem by which it is pivotally mounted on the operating lever for oscillation about a fore-and-aft axis midway between the two fingers of the'pair, the bearings for said spindles in the oper-ating lever being symmetrically disposed at opposite sides of a-fore-and-raft line through the fulcrum of the operating leverand1thepoint of application of pressure thereto. v

In testimony whereof, I have hereunto set my hand at chicago, Illinois, this 21st day of November, A. D. 1906.

' -JoHN '1c-STEWART. 

